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Whenever I try to open an attachment I get "The download cannot be saved because an unknown error occurred"

Title says it all. If I try to "open" an attachment, the download dialogue comes up and the progress bar begins to fill, then when it should be complete I get the message:

"The download cannot be saved because an unknown error occurred

Please Try Again."

I can still save the files, but then I have to delete them (and that's just a hassle). Any help would be appreciated!

Title says it all. If I try to "open" an attachment, the download dialogue comes up and the progress bar begins to fill, then when it should be complete I get the message: "The download cannot be saved because an unknown error occurred Please Try Again." I can still save the files, but then I have to delete them (and that's just a hassle). Any help would be appreciated!

Chosen solution

Don't have an anti-virus. However, I figured out what the problem was!

It seems that it wasn't actually affecting all attachments, just *.pdf files (I didn't realize it since I typically only get pdf attachments).

The problem was that my default pdf reader was set to a plug-in that wasn't working. I changed it and all is fine.

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All Replies (4)

tried with the attachment scanning in your anti virus program disabled

Chosen Solution

Don't have an anti-virus. However, I figured out what the problem was!

It seems that it wasn't actually affecting all attachments, just *.pdf files (I didn't realize it since I typically only get pdf attachments).

The problem was that my default pdf reader was set to a plug-in that wasn't working. I changed it and all is fine.

Tools, Options, Attachments, Incoming. Then set to your prefered PDF reader.

An update has reset this to the internal PDF viewer rather than sticking with the one you had before. This reader does not work on my machine.

I had the same problem with Thunderbird 31.5.0 on a Win 8.1 machine.

It wouldn't open a .jpg file but gave the "unknown error problem."

Solution:

I opened "Tools/Options/Attachments" and "Use Windows Photo Viewer" was the default for JPEGs. I selected to "Use Internet Explorer" and then I could view .jpg files from Thunderbird.

Then I switched back to "Use Windows Photo Viewer" and the .jpgs opened OK.

Something isn't getting set up right with the default option.

Phil